1. Field of the Invention
The present invention relates to an organic light emitting diode (OLED) and a method of fabricating the same and, more particularly, to an OLED in which an intermediate layer is formed between a first hole transport layer (HTL) and a second hole transport layer.
2. Description of the Related Art
An organic light emitting diode (OLED) is an emissive display that is made ultrathin and lightweight and can be fabricated in a simple process using a small number of components. Also, the OLED has high resolution and a wide viewing angle and is capable of displaying a realistic moving image with high color purity. Furthermore, the OLED can be driven at low power and low voltage and is adequate for a mobile display device in terms of its electrical properties.
In a conventional OLED, a pixel electrode is disposed on a substrate with a suitable control device (e.g., a thin film transistor), an organic layer having at least an emission layer (EML) is disposed on the pixel electrode, and an opposing electrode is disposed on the organic layer.
In order to facilitate injection or transport of holes from the pixel electrode to the emission layer, the organic layer may further include a hole injection layer (HIL) or a hole transport layer (HTL) between the pixel electrode and the emission layer.
Currently, a lot of research has been conducted on improving the efficiency and life span of OLEDs. However, the conventional hole injection layer and hole transport layer have a specific technical limit that limits how much the efficiency and life span of the OLEDs can be improved.